Vertical shaft impact (VSI) crushers find widespread use for crushing a variety of hard materials, such as rock, ore, demolished constructional materials and the like. Typically, a VSI crusher comprises a housing that accommodates a horizontally aligned rotor mounted at a generally vertically extending main shaft. The rotor is provided with a top aperture through which material to be crushed is fed under gravity from an elevated position. The centrifugal forces of the spinning rotor eject the material against a wall of compacted feed material or specifically a plurality of anvils or retained material such that on impact with the anvils and/or the retained material the feed material is crushed to a desired size.
The rotor commonly comprises a horizontal upper disc and a horizontal lower disc. The upper and lower discs are connected and separated axially by a plurality of upstanding rotor wall sections. The top aperture is formed within the upper disc such that the material flows downwardly towards the lower disc between the wall sections and is then ejected at high speed towards the anvils. A replaceable distributor plate is mounted centrally on the lower disc and acts to protect it from the material feed. Example VSI crusher distributor plates are described in WO 95/10359; WO 01/30501; US 2006/0011762; US 2008/0135659 and US 2011/0024539.
Due to the abrasive nature of the crushable material, the distributor plate is subject to substantial abrasion wear and requires servicing or replacement at regular intervals. Due to the size and weight of the plate it is a generally difficult task to handle the plate and install and remove it at the rotor. WO 2008/147274 and WO 2011/025432 describe modular distributor plates that may be introduced and removed from the rotor in smaller sections to greatly facilitate handling. However, whilst being advantageous to reduce health and safety risks, such plates can be difficult to assemble and dismantle within the rotor as access via the crusher inspection hatch is typically restricted. Accordingly, what is required is a distributor plate that addresses the above problems.